Possible Duplicate:
How do I print a double value with full precision using cout?可能重复:如何使用cout以完全精度打印double值?
float a = 175.;
cout << a;
If I run the previous code I'll get just 175, how can I cout the number with (for example) 3 decimal places even they were zeros .. How can I print "175.000" ?!
如果我运行前面的代码我将只得到175,我怎么能用(例如)3个小数位来输出数字,即使它们是零...我怎么能打印“175.000”?
2 个解决方案
#1
38
You need std::fixed and std::setprecision:
你需要std :: fixed和std :: setprecision:
std::cout << std::fixed << std::setprecision(3) << a;
These require following header:
这些需要以下标题:
#include <iomanip>
#2
4
Try setprecision:
cout.setf(ios::fixed);
cout << setprecision(3) << a << endl;
#1
38
You need std::fixed and std::setprecision:
你需要std :: fixed和std :: setprecision:
std::cout << std::fixed << std::setprecision(3) << a;
These require following header:
这些需要以下标题:
#include <iomanip>
#2
4
Try setprecision:
cout.setf(ios::fixed);
cout << setprecision(3) << a << endl;